FR2990867A1 - Auto-injector for injection of fluid product in body for treatment of e.g. disease, has sleeve actuator automatically brought back to projected position, where actuator is locked in projected position and inhibits any other actuation - Google Patents

Abstract

The auto-injector has a lower body (10) receiving a tank. The tank contains a fluid product and comprises a piston and a needle such as a prefilled syringe (A). A sleeve actuator (11) is provided in a projected position before and after actuation of the auto-injector. An injection unit e.g. piston rod, is arranged to retract the needle. The sleeve actuator is automatically brought back to a projected position when the user withdraws the auto-injector from the body. The sleeve actuator is locked in the projected position and inhibits any other actuation of the auto-injector.

Description

The present invention relates to an autoinjector. Auto-injectors are well known in the state of the art. These devices are primarily intended to achieve an automatic injection of the contents of a syringe inside the body of a patient. Various systems exist to make automatic the penetration of the needle into the patient's body as well as the injection of the fluid contained in the syringe. Auto-injectors are relatively complex devices that must meet a number of constraint requirements to be reliable. The robustness of the device, its maneuverability, and its ease of use for the user are also important elements. Moreover, most of these autoinjectors are single-use, the cost of manufacturing and assembly is also a factor to consider. There are many autoinjectors on the market, all of which have a number of disadvantages.

Thus, to avoid inadvertent tripping of the autoinjector, for example during transport or during storage, the devices must include reliable locking means. Similarly, when a user wants to use the autoinjector and unlocks the device, for example by removing the cover, the device must not be triggered inadvertently but only when the user really wants, c that is to say at the moment when he applies it against the part of the body in which he wants to perform the injection. However, especially when people using the autoinjector are elderly or disabled, it may happen that the user drops the device when he wants to use it. It is desirable that in such a case the autoinjector does not trigger itself. It is therefore important to have a reliable release lock. On the other hand, the use of the autoinjector should not become too difficult, which would prevent weak people from using it. It is therefore difficult to find the right compromise between the safety of the locking and the ease of use and actuation of the autoinjector. It is one of the objectives of the present invention to respond to this problem.

Moreover, depending on the volume of the fluid product dispensed during the injection and also as a function of its viscosity, the time required to perform this injection can be quite large, which may especially exceed several seconds. It is therefore very important that the user does not remove the device from his body before the injection is complete. It is therefore desirable that the device comprises means for reliably indicating to the user that the injection is complete. It is also important to ensure that the product is injected at the proper depth in the body, that is, in the right tissue. The control of the beginning of injection, to ensure that it will start only when the needle has reached its final stitching position, is also an important aspect. In addition, to avoid any risk of injury after use of the device, the autoinjector must include a needle safety device that prevents the needle remains not apparent after use of the device. This safety device must obviously also be reliable and not be released too easily. It must also be functional even if the user actuates the autoinjector badly, for example if he withdraws it too early from his body, before the end of the injection.

Another important aspect with autoinjectors, especially when the volume of fluid product is relatively large and / or when the fluid injected is relatively viscous, is to allow the product to diffuse from the injection site for a few seconds after said injection. If the user removes the autoinjector immediately after the end of the injection, part of the product can emerge from the body of the user which decreases the effectiveness of the treatment. It is therefore desirable to provide that the user maintains the autoinjector against his body for a few seconds after the end of the injection. This aspect is generally solved by the existing autoinjectors by the user manual which requires the user to count in his head a number of seconds before removing the device. This is not reliable and therefore unsatisfactory, because the system then depends on the user himself, which in some cases may be disrupted or weakened by the injection action he has just made. The present invention aims to provide an autoinjector which does not reproduce the aforementioned drawbacks, and which makes it possible to meet the various requirements and constraints important for safe and reliable use of the autoinjector. Another object of the present invention is to provide an autoinjector which is reliable in use, which makes it possible to guarantee the distribution of all the fluid product at the desired location, which enables the user to determine when to withdraw or when he can remove the autoinjector from his body after use, which is safe and which prevents any risk of injury, and which is simple and expensive to manufacture and assemble. The subject of the present invention is therefore an autoinjector comprising a lower body receiving a reservoir, said reservoir containing fluid and comprising a piston and a needle, such as a pre-filled syringe, said autoinjector comprising: a device for moving the reservoir; reservoir for on the one hand moving the needle to an injection position in which it is inserted into the user's body and on the other hand retracting said needle from the body of the user after injection of the fluid, an actuator sleeve provided with a contact end intended to come into contact with the body of the user, said actuator sleeve being movable between a projected position and an actuating position, said actuator sleeve being in the projected position before and after actuating the autoinjector, said actuator sleeve, in actuating position, actuating said reservoir moving device to move needle towards its injection position, - injection means for injecting said fluid product through said needle when said needle is in the injection position, - an injection lock for blocking said injection means, said tank moving device unlocking said lock and actuating the injection means when the needle is in the injection position, - wherein said injection means actuate said reservoir moving device after injection of the fluid product to retract said needle and in which said actuator sleeve is automatically returned to the projected position when the user removes the autoinjector from his body, said actuator sleeve then being locked in this projected position, preventing any further actuation of the autoinjector. Advantageously, the autoinjector comprises an outer shell having at least one viewing window to indicate the sequences of actuation of the autoinjector to the user. Advantageously, said reservoir displacement device comprises a control slider axially displaceable in said autoinjector during actuation, said control slider comprising at least one indicator, such as a color zone, visible through said at least one window of viewing. Advantageously, said injection means actuate a trigger which actuates the retraction of the needle after a predefined rotation, said trigger comprising at least one indicator, such as a color zone, visible through said at least one viewing window. Advantageously, said outer shell comprises a first viewing window indicating to the user that the injection of the fluid product is complete and that the needle is in the retracted position. Advantageously, said outer shell comprises a second viewing window indicating to the user that the stitching phases of injection of the fluid product are in progress. Advantageously, said outer shell comprises a third viewing window indicating to the user that the actuator sleeve is in the projected position.

Advantageously, the autoinjector comprises a delay device adapted to delay for a predetermined time the actuation of said reservoir displacement device by said injection means after injection of the fluid product, to delay the retraction of said needle of said predetermined time after the end. of the injection. Advantageously, said outer shell comprises a viewing window indicating to the user the flow of said predetermined time.

These and other features and advantages of the present invention will appear more clearly in the following detailed description, with reference to the accompanying drawings, given by way of non-limiting examples, and in which: FIG. 1 is a diagrammatic view in exploded perspective of the components of an autoinjector, according to an advantageous embodiment, Figures 2a to 2f are schematic cross-sectional views illustrating the various sequences of use of the autoinjector of Figure 1, Figures 3a to 3c 3 are a detailed view showing the actuator sleeve in the position of FIG. 3a. FIGS. 5 and 6 are views. FIG. diagrams in cross-section according to two different section planes showing the actuator sleeve in the position of FIG. Figures 7 and 8 are diagrammatic perspective views partially cut away showing the actuator sleeve in the position of Figures 5 and 6, Figure 9 is a view similar to that of Figure 4, at the beginning of actuation of the autoinjector, during 10 to 11 are views similar to FIGS. 5 and 6, in the position of FIG. 9; FIG. 12 is a view similar to that of FIG. 8, in the position of FIGS. 10 and 11; 13 is a view similar to that of FIGS. 4 and 9 during actuation, in the injection phase. FIGS. 14 and 15 are views similar to those of FIGS. 10 and 11 showing the position of FIG. FIG. 16 is a view similar to that of FIG. 12, showing the position of FIGS. 14 and 15. FIG. 17 is a view similar to that of FIG. 13, at the end of actuation, when the user removes the injection site autoinjector, Figure 18 is a view FIG. 19 is a schematic exploded perspective view illustrating an advantageous injection lock. FIG. 20 is a diagrammatic cross-sectional view of the injection lock of FIG. FIG. 21 is a view similar to that of FIG. 20, in the unlocking position; FIG. 22 is a schematic view from above in horizontal section of the injection lock of FIG. 19; Fig. 23 is a schematic partially cut-away perspective view of the injection lock of Fig. 19 in the locked position. Fig. 24 is a schematic cross-sectional view of the injection lock of FIG. FIG. 25 is a view similar to that of FIG. 23, in the unlocking position, FIG. 26 is a view similar to that of FIG. 24 in unlocking position, FIG. FIG. 27 is a diagrammatic perspective view of an advantageous retarder device. FIG. 28 is a diagrammatic cross-sectional view of the retarder device of FIG. 27 before it is actuated. FIG. 29 is a diagrammatic sectional view along the line of FIG. FIG. 30 is a diagrammatic sectional view along section line Y of FIG. 28; FIG. 31 is a view similar to that of FIG. 28, at the end of actuation of the delay device; FIG. 32 is an exploded schematic perspective view of an advantageous syringe displacement mechanism. FIGS. 33 to 35 are schematic partially cut-away perspective views of the displacement mechanism of FIG. 32, before actuation, in three different orientations, FIGS. 36 and 37 are views similar to FIGS. 33 and 35, during actuation of the displacement mechanism. FIGS. 38 to 41 are diagrammatic views partially cut away partial view of the moving mechanism of FIG. 32, when the needle of the syringe has reached its injection position in the body of the user, FIGS. 42 and 43 are schematic views of the moving mechanism FIG. 44 is a schematic view of the movement mechanism of FIG. 32 at the beginning of retraction initiated by the actuator sleeve, and FIGS. 45 and 46 are views similar to FIGS. 43 and 44, at the end of the injection. The autoinjector will be described below with reference to an advantageous embodiment thereof which is that shown in the figures. It should be noted that this autoinjector, which is a complex device, includes several modules to perform several functions. These various modules can be used separately and independently of each other, without necessarily being combined with other modules, and could in particular be used in autoinjectors of different shape from that shown in the drawings. Referring to Figure 1, the various components of the autoinjector, according to an advantageous embodiment, are shown in an exploded manner. In this embodiment, and in the order of numerical references, the autoinjector comprises a central body 1, a control ring 2, a quill spring 3, a control sleeve 4, a piston rod 5, a support pad 6, three locking elements 7, here in the form of balls, an injection spring 8, a control slider 9, a lower body 10, an actuator sleeve 11, a spring 12 of the actuator sleeve 5, a tank housing 13, a hood 14, an upper body 15, a plurality of sun gears 16, a plurality of satellites 17, a delay spring 18, a trigger 19, a locking pin 20, a wire 21, an outer shell 22 and a locking ring 23. All of these elements are part of the described embodiment, but not all of them are indispensable to the operation of the autoinjector, as will be more specifically described below. The cover 14 allows in particular to lock the autoinjector during transport and storage. As long as this cover is assembled on the lower body 10, it prevents any actuation of the actuator sleeve 11, and therefore any triggering of the autoinjector. A tank A can be inserted into said autoinjector. This reservoir contains fluid, and comprises a piston and a needle. The piston is adapted to move in said reservoir to inject the fluid through said needle. The present description will be made with reference to a syringe A, which may be of any type. More generally, it is understood that the term "syringe" in this specification encompasses any type of tank associated with a needle. Preferably, the syringe A is a pre-filled syringe. It advantageously comprises a needle cap B which protects and isolates the needle before use of the autoinjector. Advantageously, this needle cap B is automatically withdrawn when the hood 14 is withdrawn from the lower body 10. FIGS. 2a to 2f illustrate the sequences of the use of the autoinjector of FIG. 1. In the FIG. 2a, the autoinjector is in the rest position before use, the cover 14 having been removed.

When the user wants to use the autoinjector, he takes the device, for example at the outer shell 22 and he presses the actuator sleeve 11, which in the projected position projects out of the lower body 10, against the part of the body where he wants to make the injection. In FIG. 2b, it can be seen that the pressure exerted by the user on the actuator sleeve 11 causes the latter to slide towards the inside of the lower body 10, with the effect of compressing the spring of the actuating sleeve 12. When the actuator sleeve 11 reaches its actuating position, which is its end position inside the lower body 10, it causes the release of the stitching lock and thus the displacement of the control sleeve 4 in the lower body 10 under the effect of the quilting spring 3, with the result that the syringe A is displaced in the lower body 10 and thus the syringe needle is inserted into the body of the user, as can be seen in FIG. 2c.

When the needle reaches its injection position with full insertion of the needle, the injection phase is triggered, which is shown in Figures 2c and 2d. It is found that the piston rod 5 slides inside the syringe A pushing the piston thereof under the effect of the injection spring 8. The product is distributed.

At the end of the injection, and possibly with a certain delay or time shift as will be described later, the autoinjector provides a retraction of the syringe A. The needle is retracted out of the body of the user to the inside the autoinjector, as shown in Figure 2e.

At the end of retraction, the actuator sleeve 11 is again moved out of the lower body 10 towards its projected position, under the effect of the spring 12 of the actuator sleeve, with a locking of said actuator sleeve 11, which guarantees absolute safety for the user and avoids any risk of injury with the needle after use of the device.

An advantageous actuator sleeve will be described hereinafter in greater detail with reference to Figs. 3a-18. Said actuator sleeve 11 includes a flexible tab 110 which has dual flexibility. It is, on the one hand, radially flexible, that is to say that it deforms towards the inside of the actuator sleeve 11. It is then also laterally flexible, that is to say that it deforms in the peripheral direction of the actuator sleeve 11. An actuator sleeve 11 provided with such a flexible tab is simple to mold, which is favorable from the point of view of manufacturing costs. The flexible tab 110 advantageously comprises a rod portion 111 which is flexible and which ends with a head portion 112. Said flexible tab 110 is adapted to deform both radially and laterally laterally relative to said body. central 1 when said actuator sleeve 11 is moved from its projected position to its actuating position and its actuating position back to its projected position. Preferably, said flexible tab 110 is radially deformed when said actuator sleeve 11 moves from its projected position, prior to actuation, to its actuating position, and said flexible tab is laterally deformed when said actuator sleeve 11 moves from its position. actuation towards its projected position, at the end of use. It is this variant which is represented in the figures. FIGS. 3a, 3b and 3c are three partial schematic perspective views which show the end positions of the actuator sleeve 11, namely in FIG. 3a the projected position at rest before actuation, in FIG. 3b the actuating position wherein the actuator sleeve 11 has been inserted as far as possible into the lower body 10, and in FIG. 3c the projected position with the actuator sleeve 11 locked relative to the lower body 10, at the end of use. It is found that the central body 1 has cutouts forming grooves and shoulders which are detailed below. The central body 1 is fixed to the lower body 10 and the actuator sleeve 11 is slidably disposed within said lower body 10. The central body 1 comprises a first substantially axial groove 101 and an opening 103 separated from said first groove 101 and 2 99086 7 11 disposed in the axial extension of said first groove 101. Said central body 1 also comprising a radial cam 102 disposed between said first groove 101 and said opening 103. As can be seen in particular in Figures 6 and 7 said radial cam 102 may be formed by inclined radial thickening of the wall of the central body 1, said thickening being formed at the axial end of the first groove 101. Said radial cam 102 cooperating with said head 112 of said flexible lug 110 for radially deforming said flexible tab 110 and thus allowing said head 112 to pass from said first groove 10 to said opening 103 during the displacement of the actuator sleeve 11 towards its actuating position. Said central body 1 comprises a final receiving zone 105 offset axially and laterally with respect to said opening 103. As can be seen in the figures, this final receiving zone 105 is disposed axially approximately at the level of said first groove 101. 103 is connected to said final receiving zone 105 by a laterally inclined groove 104. An axial shoulder 106 is provided between said final receiving zone 105 and said inclined groove 104. Thus, when said actuator sleeve 11 returns from its actuating position 20 towards its projected position, said head 112 of the flexible tab 110 slides in said laterally inclined groove 104, thereby laterally deforming said flexible tab 110. When said actuator sleeve 11 reaches its projected position, after use, said head 112 comes into contact with it under said axial shoulder 106, thereby locking said actuator sleeve 11 relative to to said central body 1 and relative to the lower body 10. From this locked position, said actuator sleeve can no longer be moved towards its actuating position, from the stop formed between the head 112 of the flexible tab 110 and axial shoulder 106. Figures 4 to 8 show the starting position, i.e., when the user will start using the autoinjector. It is seen in these figures that the head 112 is disposed in said axial groove 101 of the central body 1. When the actuator sleeve 11 slides inwardly of the lower body 10, said head 112 of the flexible lug 110 will slide inside. of said groove 101 of the central body. When the head 112 reaches the axial end of the first groove 101, said radial cam 102 will cooperate with said head 112. This radial cam 102 will therefore deform the flexible tab 110, and in particular its stem portion 111, radially towards the interior towards its longitudinal central axis. Figures 9 to 12 illustrate the position in which the flexible tab 110 is radially deformed. As can be seen in particular in FIG. 11, after this radial deformation, the head 112 of the flexible lug 110 will continue to move axially for a further distance until it reaches said opening 103. The actuator sleeve 11 then reaches its operating position. as shown in Fig. 13. In this actuating position, the flexible tab 110 resiliently returns to its radially undeformed position. The head 112 of the flexible tab 110 then enters inside said opening 103 as visible in FIG. 14. The radial deformation of the flexible tab 110, necessary to move the actuating sleeve from its projected position to its actuated position , generates some resistance. Combined with the compression force of the spring 12, this resistance forces the user to exert at least a predetermined force to effect the displacement of the actuator sleeve 11 inside the lower body 10. This avoids any risk of accidental actuation or not desired after removal of the cover 14. The actuation takes place only if the user exerts said predetermined force on the actuator sleeve 11. This force threshold also creates a certain precompression in the hand of the user, with the effect that when this threshold is reached, the movement of the actuator sleeve 11 towards its actuating position is guaranteed. When the actuator sleeve 11 reaches its actuating position, that is to say in the position of FIGS. 13 to 16, the spring 12 of the actuating sleeve has been compressed and the stitching lock is triggered by said actuator sleeve 11, as will be more fully described later, which causes the movement of the syringe A inside the lower body 10 and thus the stitching of the needle into the body of the user. During all this stitching phase as well as during the injection phase following said stitching phase, the actuator sleeve 11 does not move relative to the lower body 10, since the user maintains his pressure on the part of the body in which he performs the injection. At the end of use, when the user withdraws the autoinjector from his body, the spring 12 of the actuator sleeve 11 will urge said actuator sleeve 11 back from its actuating position to its projected position, as shown. in Figure 3c. During this axial displacement back of the actuator sleeve 11 in the lower body 10, the head 112 of the flexible lug 110 will cooperate with the inclined groove 104 as visible in Figures 17 and 18. This will cause an elastic deformation of the flexible lug 110, and in particular of its shaft portion 111, as the actuator sleeve 11 will slide axially, the head 112 sliding in said inclined groove 104 laterally deforming said flexible tab 110 as clearly visible in Figure 17. This groove inclined 104 ends in a final receiving zone 105 provided with an axial shoulder 106. At the end of the return stroke of the actuator sleeve 11, the head 112 of the flexible tab 110 will enter this final receiving zone 105 and the upper edge 114 of the head 112 will come to cooperate with the axial shoulder 106, which will block the actuator sleeve 11 relative to the lower body 10. The action sleeve neur 11 can no longer slide axially inwardly of the lower body 10, 25 and the safety device is then in the locked end position. Thus, the needle is completely protected after use and the user can no longer use the autoinjector or injure himself with the needle. Of course, the shapes of the grooves, their dimensions and their inclinations can be modified according to the needs and the desired characteristics for the needle safety device. The actuator sleeve described above is particularly effective and reliable, while being robust and easy and therefore inexpensive to mold.

FIGS. 32 to 46 more particularly describe the device for moving the syringe in the lower body 10. This displacement device ensures, on the one hand, the stitching, that is to say the insertion of the needle into the body of the user, and secondly the retraction of the needle after injection. As we have seen previously, at the beginning of actuation, the syringe A is moved axially in said lower body 10 to carry out the insertion of the needle into the body of the user. After injection of the fluid product into the body of the user, and possibly after a certain delay provided by the retarding device described above, the syringe A is again moved in the other direction inside the lower body 10, to be retracted and thus automatically remove the needle from the body of the user. In this way, when the user removes the autoinjector from his body, the needle is no longer projecting but instead retracted inside said autoinjector. To perform these movements back and forth of the syringe A in the lower body 10, there is provided a control ring 2 which cooperates with the control sleeve 4, with the control slider 9 and with the actuator sleeve 11. Furthermore, the trigger 19 intervenes to achieve the retraction of the syringe inside the body as will be explained below. Figures 33 to 35 illustrate the starting position before the syringe is moved for tapping. It is found that the control ring 2 is urged in rotation by the stitching spring 3, which here is a spring acting in torsion. Such a torsion spring makes it possible to perform a non-painful stitching. In this initial position of Figures 33 to 35, the rotation of the control ring 2 is prevented by a projection 91 of the control slider 9, as more clearly visible in Figure 35.

When the actuator sleeve 11 arrives at its end position inside the lower body 10, as shown in FIG. 3b, a shoulder 118 of said actuator sleeve 11 will cooperate with a shoulder 92 of the control slider 9 to move axially said control slide 9 upwards in FIG. 36. This axial displacement of the control slide 9 will release the rotation of the control ring 2 which will be able to rotate under the effect of its loaded pricking spring 3. The control ring 2 comprises three inclined profiles 24, 25, 26 similar to ramps, whose functions will be explained below. The control ring 2 comprises a first inclined inner profile 24, such as a ramp, which will cooperate with a projection 44 of the control sleeve 4. Thus, the rotation of the ring 2 will progressively move axially said control sleeve 4. This control sleeve 4 cooperates with the syringe housing 13 which receives the syringe, and thus a displacement of the control sleeve moves the syringe A into the lower body 10 to perform the stitching of the needle.

Figure 39 illustrates the position in which the needle is fully inserted, with the first inclined profile 24 which cooperates with the projection 44 of the control sleeve 4. During the displacement of the control sleeve 4 and thus the insertion of the needle in the body of the user, the projection 91 of the control slider is also in contact with an external inclined profile 25 of the ring 2, such as an external ramp, which will cause additional axial movement of said control slider 9 by relative to the actuator sleeve 11. This will move the control slider 9 in the same direction as the actuator sleeve 11 during stitching. As a result, the projection 92 of the control slide 9 comes close to an upper projection 119 of the actuator sleeve 11, and the projection 95 of the control slide 9 comes close to a projection 191 of the trigger 19, as can be seen in FIG. 44. The first internal inclined ramp 24 which cooperates with the projection 44 of the control sleeve 4 advantageously comprises a plate 241, that is to say a non-inclined portion, visible in FIG. 41. This plate 241 has a very important function. important since it ensures that the beginning of the injection will occur only after the complete end of the needle insertion into the body of the user. While for many autoinjectors it is necessary to start the injection a little before the needle reaches its final insertion point, for reasons of manufacturing tolerance, the plate 241 on the ramp 24 avoids this. phenomenon. Indeed, while the ring 2 has already completely moved the control sleeve 4 axially and thus has achieved the total insertion of the needle of the syringe into the body of the user, it is necessary that the ring 2 turns again. on the arc formed by said flat, for example about 30 °, to trigger the injection lock. Thus, the locking ring 23 of the injection lock is moved out of its locking position only after the additional rotation of the ring 2 on the arc formed by said plate 241. During this additional rotation, there is no axial displacement of the control sleeve 4, and therefore of the syringe A, since the plate 241 is not inclined.

Even with manufacturing tolerances, it is thus ensured that the insertion is completed before the injection begins. Meanwhile, during this additional rotation of the control ring 2, a second internal inclined profile 26, such as a ramp, of the control ring 2 will cooperate with a projection 235 of the locking ring 23 of the injection lock. and move the latter out of its locking position to release the injection, when the control ring 2 reaches the end of its additional rotation. This is also visible in FIG. 41. Advantageously, the control ring 2 comprises three second internal inclined profiles 26 arranged at 120 ° from each other, and the locking ring 23 comprises three projections 235 also arranged at 120 ° others, a respective projection 235 cooperating with a respective second inner inclined profile 26. When the injection is triggered by the locking ring 23, the rotation of the control ring 2 is again blocked by the control slider 9. With the control slider 9 in the position of FIG. 44, if the user removes the autoinjector from its body while the injection is in progress or after injection but before the end of the self-timer, the spring 12 of the actuator sleeve 11 will urge said actuator sleeve 11 back out of the lower body 10. This movement of the sleeve actuator 11 will pull the control slider 9 axially downwards in FIG. 44 by the cooperation between the upper shoulder 119 and the projection 92 of the slider. Thus, the control ring 2 will again be released in rotation by the control slider 9, and the spring 3 will urge this control ring further in rotation which will cause the retraction of the syringe and the needle to the inside the body. The actuator sleeve 11, at the end of movement, will be locked as previously described. Thus, even if the user removes the autoinjector before the end of dispensing the product, the needle safety device is operative. In normal operation, the injection ends and as will be described below, the piston rod 5 will release the rotation of a trigger 19, possibly with a certain delay if a delay device is used. From the moment when the trigger 19 has made a predefined rotation, a projection 191 of the trigger 19 will cooperate with the upper shoulder 95 of the control slider 9, and the control slider 9 will be moved axially downwards in FIG. 44, which will release the rotation of the control ring 2 as previously described. Figures 45 and 46 illustrate the retraction of the needle with the rotation of the ring 2 which will bring the projection 44 of the control sleeve facing an internal groove of the ring 2, which will cause, under the effect of the spring, the axial displacement back of the control sleeve 4 inside the control ring 2 and thus the retraction of the syringe and the needle. Figures 19 to 26 schematically illustrate an advantageous injection lock. The autoinjector comprises injection means, comprising in particular the piston rod 5, the injection spring 8 and the locking ring 23, these injection means being locked in a position loaded by said injection lock. The unlocking of said injection lock then causes the actuation of said injection means and thus the injection of the fluid product through the needle. As shown in FIG. 19, said injection lock comprises a control sleeve 4 disposed in said central body 1, said control sleeve 4 containing said piston rod 5 and said injection spring 8, said piston rod 5 comprising a radial recess 50 receiving at least one locking element 7 movable between a locking position and an unlocking position. In the variant shown there are three locking elements 7 in the form of balls, but a different number of locking elements and different shapes of these locking elements are possible. The following description will nevertheless be made with reference to three balls, without this being limiting. Said balls 7 are biased radially outwardly by said piston rod 5 and are retained in the locking position by a locking ring 23. This locking ring 23 is axially displaceable relative to said control sleeve 4 to release said balls 7 and thus unlocking said injection lock, enabling said injection spring to move said piston rod 5 towards its injection position. Figure 20 shows the injection lock in the locking position.

The injection spring 8 cooperates on the one hand with the piston rod 5 and on the other hand with a support pad 6. This support pad 6 is formed by a ring disposed around said piston rod 5. The piston rod 5 comprises a peripheral recess 50, advantageously provided with an inclined surface 51, formed by a narrowing of the diameter of said piston rod 5. This piston rod 5 is disposed inside the control body 4 and is capable of move axially to the left in FIG. 20 to push the plunger of syringe A inside the syringe and deliver the fluid contained in said syringe through the needle.

As can be seen in FIG. 20, the balls 7 are disposed in said recess 50 formed in the piston rod 5 and thus cooperate with the inclined wall 51 of the piston rod 5 and with the upper surface on the one hand. 61 of said support pad 6. The inclined surface 51 of the piston rod is in contact with the balls 7 so that under the effect of the compressed spring 8, said inclined surface 51 exerts a reaction force F1 on the balls 7, this F1 force is not exactly axial but directed slightly outwardly, thus biasing the balls 7 radially outwardly of the locking position of Figure 20. The locking ring 23 is provided radially outside the balls 7 for radially locking said balls in the locking position. Referring more particularly to FIG. 22, it can be seen that the balls may be arranged in housings of the control sleeve 4, the locking ring 23 comprising projections 231, one for each ball 7, which are positioned in contact with the balls. balls 7 to prevent them from being displaced radially outwards. The pellet 6 transmits the force F3 of the spring 8 to the balls 7, and the locking ring 23 exerts a reaction force F2 on the balls 7 to prevent a radial displacement thereof. Thus, it is the balls 7 which support all the forces exerted on the lock in the locking position, with a balance in three points under the effect of the forces F1, F2 and F3. Such a lock is particularly stable and robust, and in particular to withstand drops tests. These tests simulate the fact of dropping the autoinjector on the ground after removing the cover 14, the objective being to avoid a triggering of the injection lock during this fall. In particular, no force is exerted on the structural parts of the autoinjector, such as the central body 1 or the lower body 10. This lock thus avoids the risk of inadvertent disassembly of the device during transport or handling. It should be noted that the balls 7 could be replaced by non-spherical elements but of more complex shape, for example in the form of cylinder or bean, to further improve the stability of the lock. In this case, these non-spherical movable elements could be made of metal, for example by cutting steel wire. When the needle of the syringe has completely penetrated the body of the user, and only after this total insertion, as will be described later, the locking ring 23 is moved according to the arrow E1 in FIG. effect of releasing the balls 7 from their blocking position, these being then moved radially outwards along the arrow E2. Alternatively, the locking ring 23 could also be rotated to a position where it releases the balls. The support pad 6 then abuts against an inner edge of the control sleeve 4 as represented by the arrow E3 in FIG. 21. In this position, the piston rod 5 is no longer retained by the balls 7 and is therefore moved axially, that is to say to the left in Figure 21, to perform the injection of the product. The balls 7 can not return to the locked position, prevented by the patch 6, as shown in Figure 21. Figures 23 to 26 illustrate with slightly different views the two locking and unlocking positions of the injection lock as described above with reference to FIGS. 20 and 21. The injection lock shown in FIGS. 19 to 26 makes it possible to unlock a large force exerted by a compressed spring, in this case the injection spring 8, by exerting a relatively small force and easily controllable on the locking ring 23. In particular, the force required to move said locking ring 23 in unlocking position may represent only 10%, or even only 5%, of the force exerted by the spring 8. This represents a very important performance that guarantees easy and reliable operation of the device. When the injection is complete, that is to say when the piston rod 5 has reached its end position in which the piston of the syringe A has been moved to inject the fluid, a trigger 19 is actuated to retract the syringe and thus the needle. During the injection phase, a locking finger 20 extends through the trigger 19 and into the central channel 151 of the upper body 15.

A delay spring 18, here a spiral spring, biases said trigger 19 in rotation. This rotation is blocked by the locking finger 20, advantageously of oblong shape, which is adapted to rotate together with said trigger 19, but which is blocked in rotation by said central channel 151 of the upper body 15. During the injection phase, the piston rod 5 moves axially, that is to say to the left in FIG. 28. As it moves, it will pull on the wire 21 which will therefore extend out of the channel 151. As long as the locking finger 20 is disposed inside the central channel 151, the rotation of the trigger 19 is blocked.

When the piston rod 5 approaches the end of injection stroke, the wire 21 is completely pulled and stretched between the piston rod 5 and the locking pin 20, and any further displacement of the piston rod 5 will therefore move axially the locking pin 20 out of said central channel 151. When the piston rod 5 reaches end of injection end position, the locking finger no longer cooperates with the central channel 151, and the trigger 19 and the finger of locking can then rotate under the effect of the self-timer spring 18. As can be seen in FIG. 31, the trigger 19 comprises an inclined external ramp 190 which may comprise on one side a projection 191. When the trigger 19 has made a predefined rotation, typically about one turn, this projection 191 will cooperate with the control slider 9, which will move it axially and thus trigger the retraction of the needle, as has been described above. Figures 27 to 31 illustrate an advantageous delay device.

This delaying device, which is optional in an autoinjector, is mainly intended to shift in time the retraction of the syringe A and therefore the needle out of the body of the user after the end of the injection of the fluid product. inside said body. This allows in particular a diffusion for a few seconds of the product after its injection. Such a retarder also provides a benefit for the user, who no longer has to count, for example up to 10, after its injection, the time taken for this count can be very variable from one user to another. With a self-timer, the sequence of use of an autoinjector is facilitated. The mechanical retarder shown in FIGS. 27 to 31 makes it possible to shift this retraction a few seconds, this delay being predeterminable. Figure 27 illustrates an exploded schematic view of this delay device. This comprises the upper body 15, several planetaries 16 with several satellites 17, the delay spring 18, the trigger 19, the locking pin 20, the wire 21 and the piston rod 5. It is this piston rod 5 which will perform the actuation of the delay device when it reaches the end of the injection stroke with all the product that has been injected. Figure 28 shows the delay device before it is actuated. It can be seen that the actuating rod 5 is connected to the locking finger 20 via the wire 21. In this position, the wire 21 and the locking finger 20 extend inside a central channel 151 the upper body 15 and the trigger 19. The upper body 15 has a gear 155 on its lateral inner surface, as clearly visible in Figure 30. This internal gear 155 of the upper body 15 cooperates with a plurality of satellites 17 which are assembled 16. In the example shown in FIG. 28, there are several planetary wheels stacked axially on one another. The planet gears 16 comprise a disk-shaped plate on which satellite support rods 161 are formed on one side, each of which receives a satellite 17 in rotation. In the example shown, there are three satellites 17 on each stage. so that there are three rods 161. Each sun gear 16 associated with its satellites 17 forms a stage of the delay device. On the other side of the disk-shaped plate, the sun gear 16 has a gear 162 adapted to cooperate with the satellites 17 of the adjacent stage. Thus, as shown in FIG. 30, the delaying device uses the principle of epicyclic gear trains. Each stage of this device makes it possible to increase and / or slow down the rotations of the previous stage.

When a delay device is used, the trigger 19 cooperates with a first sun gear 16, whose rods 161 extend inside said trigger 19. The gear 162 of the first sun gear 16 then cooperates with the satellites of a second planetary adjacent, which cooperate with the lateral gear 155 of the upper body 15, thereby multiplying the rotation of the first sun gear and therefore the trigger, and thus curbing this rotation. Each additional stage of the epicyclic gear train forming the retarder will further reduce these rotations, and thus further reduce the rotation of the trigger 19. Thus, with four stages as shown in the figures, it is possible to reduce the rotation of the trigger 19 to a single revolution while the last sun gear 16 disposed at the bottom of the upper body 15 will simultaneously perform about fifty turns. Depending on the number of stages and / or on the number of satellites and / or on the shape of the sun wheels and / or on the dimensions of the gears in play, the delay between the moment when the delay device is triggered and the moment when the trigger 19 has achieved its predefined rotation to trigger the retraction of the syringe, as will be explained later. Friction braking can also be provided, for example between the satellites 17 and the internal gear 155 of the upper body 15. The delaying device thus allows to shift by a predetermined time the moment when said trigger will actuate the retraction of the needle, from the moment the injection phase is completed. It should be noted that the principle of the deployable wire connected on the one hand to the piston rod 5 and on the other hand to the locking pin 20 can be used without the epicyclic gear system as shown in FIGS. 27 to 31 This thread, which is very compact, makes it possible to ensure that the retraction of the needle does not begin until the injection phase has been completely completed, in particular by making it possible to compensate for any manufacturing tolerances. More generally, the use of a wire reduces the size of the device. Therefore, it can be used advantageously for different functions in an autoinjector, since it is necessary to draw a piece relative to another. According to one advantageous aspect, the outer shell 22 comprises several indicators that make it possible to inform the user of the progress of the quilting, injection and retraction sequences. In case of use of a delay device, it is also possible to provide a display of said delay. Thus, as can be seen in FIGS. 2a to 2f, the outer shell 22 may comprise several viewing windows, in this case three windows 221, 222, 223, which make it possible to visualize moving elements during the various phases of actuation, these elements with indicators, typically colors. Thus, the control slider 9, which at rest is in a first position with respect to the central body 1, moves axially towards a second position during the displacement of the actuator sleeve 11. It then remains in this second position during the entire phase of operation. injection, and returns to its first position when retracting the needle. Only when the actuator sleeve returns to its projected position, the control slider reaches this first position. This control slider 9 may comprise one or more color indicators, for example a red zone as visible in FIG. 1. This slider can therefore be used to indicate on the one hand the projected position of the actuator sleeve 11 (first position) and on the other hand the stitching and injection phase (second position). The trigger 19, which triggers the retraction of the needle at the end of injection, may also include an indicator, for example a red zone, which is displayed when said trigger has achieved its predefined rotation and thus actuated the retraction of the needle. Thus, the first viewing window 221 may be the end of injection window, that is to say that when a predefined color, for example red, appears in the window 221, the injection is completed and the syringe has been retracted. The user therefore knows that when this first viewing window is red, he can remove the autoinjector safely from his body. This indication may for example be provided by the trigger 19. The second viewing window 222 may be that of the stitching and injection phases, which goes red during the beginning of the stitching phase at the end of the phase of injection. This prevents the user from removing the autoinjector body during these phases, which can last several seconds. This indication may be provided by the actuator slide 9. The third viewing window 223 may be that of the actuator sleeve 11, with the red displayed when the actuator sleeve 11 is in its projected position out of the lower body. This third viewing window 223 is red before operation, then again after use, when the actuator sleeve 11 is locked in the safety position. This indication can be provided by the control slider 9.

In the example shown, the red zone of the actuator slide 9 passes from the third viewing window 223, before actuation (FIG. 2a) to the second viewing window 222 (FIG. 2c) when the actuator sleeve is in the actuating position where it triggers the stitching phase. During this transition, said red zone is not visible, being located between said windows 223 and 222 (FIG. 2b). During the stitching and injection phases, the control slider remains in its second position (Figure 2c & Figure 2d). When the control slider 9 is again moved axially towards its first position by the trigger 19, to actuate the retraction of the needle, the red zone passes back from the second window 222 to the third window 223, being again invisible (FIG. 2e), finally reappearing in the third window 223 when the actuator sleeve is locked in the projected position (FIG. 2f). In this configuration, the combination of the red in the first and third viewing windows 221 and 223 guarantees the end of the process of using the autoinjector, with the retracted needle and the actuator sleeve 11 locked, which guarantees an optimal security .

Of course, other display or indication means are also possible, and said outer shell 22 may comprise any number of viewing windows, of any shape and size, and which could be positioned differently from the represented variant. in the figures. Optionally, in the first viewing window 221 or in an additional viewing window, it is possible to display the state of the delaying device, for example with a countdown. This could be achieved for example with numerical values written on the external lateral edge of the trigger which passes gradually into an appropriate viewing window and which displays in seconds the timer count. Other variants are of course also possible. This outer shell 22 may also include one or more buttons stitching and / or retraction of the needle, if the autoinjector provides such buttons to perform the stitching and / or retraction of the needle. The outer shell 22 could also include a temperature indicator of the product to be injected. Indeed, many products to be injected are stored at 8 ° and it is often recommended to take them out 30-60 min in advance. If the product is too cold at the time of injection, this can cause pain in the patient. For example, the shell 22 could include a display of the temperature of the tank containing the product to be injected. Alternatively, it could also provide a label that changes color with temperature. This temperature indicator could be provided on the shell, or on the tank, including the syringe, and be visible through a window of the hull. The present invention is particularly applicable to the treatment of autoimmune diseases, for example of the type rheumatoid arthritis, multiple sclerosis, Crohn's disease, for cancer treatments, for antiviral treatments, for example of the hepatitis type, for treatments for diabetes, for treatment against anemia or for treatment of seizures, for example in case of anaphylactic shock.

Although the present invention has been described with reference to an advantageous embodiment thereof, which combines several functional modules, it is understood that the various modules described can be used independently of each other. In particular, the actuator sleeve and / or the syringe displacement device for tapping and / or retraction and / or the injection lock and / or the delay device could be used independently of one another. Stitching of the needle and / or retraction of the needle after injection could be controlled by one or more button (s). Other modifications are also possible for those skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims (9)

CLAIMS1.- Autoinjector comprising a lower body (10) receiving a reservoir, said reservoir containing fluid and comprising a piston and a needle, such as a pre-filled syringe (A), characterized in that said autoinjector comprises: - a reservoir displacement device (2, 4, 9) for firstly moving the needle to an injection position in which it is inserted into the body of the user and for the other hand retracting said needle out of the body of the user after injection of the fluid product, - an actuator sleeve (11) provided with a contact end intended to come into contact with the body of the user, said actuator sleeve (11) being movable between a position projected and an actuating position, said actuator sleeve (11) being in the projected position before and after actuation of the autoinjector, said actuator sleeve (11), in actuating position, actuating said actuator reservoir displacement means (2, 4, 9) for moving a needle towards its injection position; injection means (5, 8) for injecting said fluid product through said needle when said needle is in a position of injection, - an injection lock for blocking said injection means (5, 8), said tank displacement device (2, 4, 9) unlocking said lock and actuating the injection means when the needle is in injection position, wherein said injection means (5, 8) actuates said reservoir displacement device (2, 4, 9) after injecting the fluid product to retract said needle, and - wherein said actuator sleeve ( 11) is automatically returned to the projected position when the user removes the autoinjector from his body, said actuator sleeve (11) then being locked in this projected position, preventing any further actuation of the autoinjector. 2. An autoinjector according to claim 1, comprising an outer shell (22) having at least one viewing window (221, 222, 223) for indicating the sequences of actuation of the autoinjector to the user. 3. An autoinjector according to claim 2, wherein said reservoir displacement device comprises a control slider (9) axially displaceable in said autoinjector during actuation, said control slider (9) comprising at least one indicator, such as an area of color, visible through said at least one viewing window. 4. An autoinjector according to claim 2 or 3, wherein said injection means actuate a trigger (19) which actuates the retraction of the needle after a predefined rotation, said trigger (19) comprising at least one indicator, such as an area of color, visible through said at least one viewing window. 5. An autoinjector according to any one of claims 2 to 4, wherein said outer shell (22) comprises a first viewing window (221) indicating to the user that the fluid injection is complete and that the needle is in the retracted position. 6. autoinjector according to any one of claims 2 to 5, wherein said outer shell (22) comprises a second viewing window (222) indicating to the user that the stitching phases of fluid injection are In progress. An autoinjector according to any one of claims 2 to 6, wherein said outer shell (22) has a third viewing window (223) indicating to the user that the actuator sleeve (11) is in the projected position. 8. An autoinjector according to any one of the preceding claims, comprising a delay device (15, 16, 17, 18, 19, 20, 21) adapted to delay for a predetermined time the actuation of said tank displacement device (2 , 4, 9) by said injection means (5, 8) after injection of the fluid product, to delay the retraction of said needle of said predetermined time after the end of the injection. An autoinjector according to claim 8, wherein said outer shell (22) includes a viewing window indicating to the user the flow of said predetermined time.